“My mom has been McDougalling for some time
and her doctor is unhappy with her HDL being low, although her LDL is also
low.” writes Monica on my discussion board (September 24, 2003).

There is a lot of
confusion today about HDL-cholesterol, or high density lipoproteins,
commonly referred to as "good" cholesterol. HDL-cholesterol is one
fraction of total cholesterol (other fractions are classified as VLDL
(very low-density lipoprotein), LDL (low-density lipoprotein), and MDL
(medium-density lipoprotein). When total cholesterol is lowered, all
fractions of cholesterol are reduced, including HDL-cholesterol. This
is not bad, but expected, and actually of no harm. One simple way to
raise HDL-cholesterol is to eat more meat (cholesterol) – but that’s not
good, because you also increase your risk of heart disease.

(If you are
having trouble understanding this concept, then this analogy may help.
Imagine cutting a watermelon (representing the total cholesterol) in half
– you now have half as much of all the parts of the melon, including half
the number of seeds (HDL). Now double the size of your original watermelon
and you now have twice as many seeds.)

Here is a classic
experiment demonstrating how eating cholesterol raises cholesterol in the
blood. An "affluent" high-fat, high-cholesterol diet was substituted for
five weeks for the traditional near-vegetarian diet of a group of 13
Tarahumara Indians – a Mexican people known to have virtually no coronary
heart disease. Cholesterol levels increased by 31 percent (121 to 159
mg/dl), LDL rose 39 percent (72 to 100 mg/dl) and their HDL-cholesterol,
usually low in this population, increased by 31 percent (32 to 42 mg/dl).1
If they had continued to eat this way they would soon have had heart
disease, like their genetic relatives, the Pima Indians, living in Arizona
on the Western diet – where 15 percent of males and 8 percent of females
aged 40 years and over have had heart attacks, and approximately half of
this population are diabetic and /or obese.2

HDL is associated
with less heart disease when comparing people who all eat an unhealthy
diet (like Americans). This is because of differences in metabolism
in people – some people more rapidly shift LDL (the form harmful to the
artery walls) to HDL (the form that leaves the body). This is fine to
have it lower, but the level is dependent upon something you have
virtually no control over – your metabolism. Other than having the
opportunity to pick out people with “better” metabolisms, knowing this
number is largely irrelevant to achieving better health.

Worldwide
(comparing people who eat different diets) those who have the lowest HDL
levels (like people in rural Japan, China, and Africa) have the lowest
rate of heart disease – and also the lowest total cholesterol.3
Those with the highest HDL levels (like people in the USA and Western
Europe) have the highest rates of heart disease. Looking at this
comparison you realize that you can change your diet and change your risk
of heart disease – such as is seen in various countries where people eat
different diets.

One group of
researchers summarized the preceding two paragraphs in one sentence, “In
assessing coronary heart disease risk, it may be inappropriate to conclude
that diet-induced decreases in HDL are equivalent to low HDL within a
given diet.”4

So What if a
Number – HDL – Is Lower or Higher?

Many people today rationalize their high total cholesterol
levels by saying that they also have high HDL levels. This
rationalization occurs not just among lay people, but also among
physicians. I have met people with total cholesterol levels of 285 mg/dl
who were told by their doctors not to worry because their "good" HDL
cholesterol is also high – 75 mg/dl or higher. Unfortunately, tens of
thousands of people have heart attacks and eventually go to their graves
each year with this false assurance ringing in their ears.

Just as HDL goes up as total cholesterol rises, so too do
HDL levels fall as total cholesterol drops. This is the case for anyone
who adopts a low-fat, low-cholesterol regimen like ours. In a study of
over 2000 of my patients, we have found that, on average, people reduce
their overall HDL levels by 19 percent (8 mg/dl – from 41 mg/dl to 33
mg/dl) in 11 days.5
(Total cholesterol also drops on average 29 mg/dl.) People on healthy
vegetarian diets are sometimes told to eat meat because their HDL is only
25 mg/dl. Yet, their total cholesterol is only 125 mg/dl – a total
cholesterol level that makes them virtually immune from heart disease.6

HDL cholesterol is a risk factor – not a disease. No one
dies of low HDL – they die of rotten arteries. Focusing on risk factors,
as the medical business does by treating blood pressure, cholesterol,
sugar, triglycerides, and homocysteine with drugs, causes little or no
improvement in health and longevity. To get the health we deserve we need
to correct the cause of the problem; an unhealthy diet and lifestyle (not
the signs of disease – the risk factors). Total cholesterol (as apposed
to the cholesterol fractions, like HDL) is the number that matters most to
me (an ideal level and your goal is 150 mg/dl or less6).
Don't be misled by partially-informed people. When you adopt the
McDougall Program, you will watch your total cholesterol fall
dramatically. As it does, both LDL and HDL levels will drop, as well.
And as they do, so too will your risk of heart disease. And your health
will improve dramatically. Unfortunately, because HDL doesn’t go up with a
healthy diet some unenlightened physicians – acting like puppets for the
pharmaceutical industry – give their patients a totally undeserved hard
time.

2) Ingelfinger
JA. Coronary heart disease in the Pima Indians. Electrocardiographic
findings and postmortem evidence of myocardial infarction in a population
with a high prevalence of diabetes mellitus. Diabetes. 1976
Jul;25(7):561-5.